Temperature-regulating bevice



L. REICHOLD.

TEMPERATURE REGULATING DEViCE.

APPLICATION mm was. 1919.

1,414,669, Patented May 2,1922.

Fig.2.

Inventor:

Ludwig Rei chold.

H is Attorn ey.

UNlTED STATES PATENT OFFICE.

LUDWIG REICHOLD, F PITTSFIELD, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

TEMPERATUBE-REGULATING DEVICE.

Specification of Letters Patent.

Patented May 2 1922.

- To all whom it may camera:

Be it known that I, LUDWIG Rnrorronn, a citizen of the United States, residing at Pittsfield, county of Berkshire, State of .Ma'ssachusetts, have invented certain new and useful Improvements in Temperature- Regulating Devices, of which the following is a specification.

My invention-relates to temperature regulating devices, and has for its object the provision of an improved device of this character. 7 a

More specifically, my invention relates to a temperature regulating device for'controlling an electrical circuit at various predetermined temperatures, in which I use a pressure coil actuated by mercury or, its equivalent thermometric material. Heretofore, much difficulty has been experienced in ob-. taining a simple and eflicient device of this character that could be set for operation at various temperatures by the use of a single pressure coil.- In such .devices it has been necessary to have a pressure coil for each desired temperature, or to have complicated structures involving the additional use of thermometers and other elements, and their operation was not dependent. solely upon the expansion'of the thermometric material actuating the pressure coil. These obje'ctions I overcome by introducing a diaphragmatic expansion chamber between the bulb and the pressure coil, all of which form a closed vacuum system containing the thermometric material. The various temperatures at which the pressure coil will operate are obtained by varying the expansion or capacity of said chamber, that is, increasing or decreasing the vacuum in which the actuating liquid or thermometric material may expand. 4

My invention is particularly adapted for the control of electric ovens .or furnaces, although it has other applications. The heating circuit for the oven or furnace may be controlled directly by the pressure coil, or indirectly through suitable relays.

The objects and purposes of my inven tion will appear in'the course of the following specification in which I have shown my invention embodied in concrete form for purposes of illustration.

In the accompanying drawings, Fig. 1 is a form of temperature regulating device em-. bodying my invention and Fig. 2 is a vertical section of the controlling, diaphragm taken on the lines 1-1 of Fig. 1.

Referring tothe drawings, 1' is abulb connected by a tube 2 to a pressure coil 3, which I have shownin the form of the ordinary Bourdon tube forming a closed vacuum sys- ,tem in which is contained an incompressible thermometric material, preferably mercury. It will be observed that the terminal 4 of said coil is secured to a pivoted member 5 which carries the movable contacts 6 and 6" of an electrical switch 6 to be c0ntrolled by the device described. 6 and 6 are fixed contacts of the switch 6. Between the bulb 1 and the coil 3, and forming a partof said closed system, is a diaphragmatic expansion chamber 7 From Fig. 2, it will be seen that the walls of this cham ber-are made from two diaphragmmembers 8 and 9 in the form of dishedplates welded together at their peripheral portions as shown. The members 8 and 9 are provided with arms 10 and 11 respectively, which in addition to supporting the diaphragmatic chamber also serve as a means for regulating the size of the vacuum therein. Said members 8 and 9 are loosely mounted in a surrounding frame consisting of two rigid arms ,12 and 13 which are hinged together at 14.

- convenience in operating said screws.

Assuming that the system was completely filled with mercury at zero temperature, an increasing temperature would cause a pressure to be transmitted through the tube 2 and chamber 7 to the coil 3 from the bulb 1 "and cause the switch to be operated in a well known'manner. But, for instance, should itbe desired that the coil 3 operate the switch 6 at 100 0., then a vacuum must be provided in the system to allow the expanding mercury to fill in, which vacuum must be equivalent to the increase in volume of the mercury at 100 C. due to expansion. It obvious thatthe pressure coil 3 would not operate the switch 6 until this vacuum was first filled. The pressure in the system will be built up quickly after the vacuum has been filled, due to the incompressibility of the thermometric material used, and the pressure coil will, consequently, be actuated with a positiye motion. The diaphragmatic expansion chamber and the volume adjusting means therefor are so constructed that the volume of the chamber, when adjusted, will not be affected by the high pressures generated by the expanding mercury. thereby effecting positive action of the pressure coil. It will, therefore, be seen that the temperature at which the coil 3 will operate may be regulated by varying the vacuum of the chamber 7 by setting the screws 15 and 16 at thedesired calibration.

\Vhile I have described my invention 'as embodied in concrete form and as operating in a specific manner in accordance with the provisions of the patent statutes, it should be understood that I do not limit my invention thereto, since various modifications thereof will suggest themselves to those skilled in the art without departing from the spirit of my invention the scope of which is set forth in the annexed claims.

\Vhat I claim as new and desire to secure by Letters Patent of the United States, is:

1. A temperature regulating device comprising a closed vacuum system containing an incompressible thermometric material, a pressure coil, and diaphragmatic expansion chamber having unyielding means cooperating with the sides thereof whereby said coil is controlled by varying the vacuum of said system to the equivalent volume of temperatures.

tween having arms extending from opposite I sides-thereof, all forming a closed vacuum system contalning an incompressible thermometric material and levers pivotally attached to said arms for varying the vacuum of said chamber to correspond to the volume of the thermometric material at various 4. A temperature regulating device comprising a closed vacuum system containing an incompressible thermometric material, a pressure coil, an electric switch operated by said coil, and a diaphragmatic expansion chamber having levers in pivotal relation with 'opposite sides thereof whereby the tem erature at which said switch is operate is controlled by varying the vacuum of said system to the e uivalent volume of the thermometricmaterial at the operative temperature.

In witness whereof, I have hereunto set my handthis fourth day of August, 1919.

LUDWIG REIcHoLi). 

